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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Potravní ekologie netopýra velkého (Myotis myotis) / Trophic ecology of the greater mouse-eared bat (Myotis myotis)

Bendová, Barbora January 2015 (has links)
In 2012 it was observed foraging ecology of the three males of greater mouse-eared bat (Myotis myotis), inhabiting individual roosts in the interior of road bridge near Bernartice, and the nearest nursery colony of the same species in the village Senožaty (district Pelhřimov). In the period April to September in Senožaty were made 14 collections at intervals of approximately 14 days and in the bridge near Bernartice at similar intervals were made 8 collections from each male in the period from May to September. From each collection were subsequently been analyzed 20 samples (pellets) by the traditional method of preparation of faeces. Overall it was from all the bats analyzed 760 samples, of which 280 from the nursery colony and 480 from males. Based on the analysis was found diet composition of individual bats and of the colony, where the overall character of the trophic niche of the greater mouse-eared bat, seasonal dynamics in it's diet composition, sex differences and individual differences between males were observed. From a point of view of it's hunting strategy the greater mouse-eared bat showed itself as a ground gleaner, in whose diet were dominated larger Coleoptera, of which the predominant component were large, flightless, mostly forest Carabidae, adding medium and smaller species of...
32

Day-roosting Social Ecology of the Northern Long-eared Bat (Myotis septentrionalis) and the Endangered Indiana Bat (Myotis sodalis)

Silvis, Alexander 08 December 2014 (has links)
Day-roost use by northern long-eared bat (Myotis septentrionalis) maternity colonies on the Fort Knox military reservation, Kentucky, USA, resulted in formation of non-random networks of roosts that exhibited a trend toward centralization. Centralization of day-roost networks was reflected in the social structure of colonies, which were characterized by dense associations among individuals within colonies. Social structure varied among colonies and appeared to be related to reproductive condition; colonies exhibited greater cohesiveness during parturition and lactation. Northern long-eared bat maternity colonies appeared to be exclusive, occupying distinct roosting areas with one or several areas receiving intense use. Day-roost removal simulations suggested a linear relationship between colony fragmentation and roost loss, and that loss of >20% of roosts is required to initiate colony fragmentation. Experimental hierarchical removal of day-roosts yielded results consistent with simulations, as removal of the single most-central (primary) roost had no impact on colony fragmentation, whereas removal of 24% of less-central (secondary) roosts resulted in partial network fragmentation. Patterns of colony day-roost and space use were similar pre- and post-removal treatments. Day-roost removal did not alter the number of roosts used by individual bats, but distances moved between roosts were greater in the secondary roost-removal treatment group. Day-roost characteristics largely were consistent pre-post treatment for both treatment groups. Historical data from an Indiana bat (Myotis sodalis) maternity colony revealed that this species also exhibits a non-random social assorting dynamic. Non-random social assortment resulted in a closely connected centralized network of day-roosts. Individuals within the Indiana bat maternity colony exhibited close social connections with colony members, but subgroups likely existed within the colony. Indiana bat day-roosting ecology appears flexible, as patterns of roost and space use differed substantially between years. Development of specific, but tactical, management approaches for individual colonies of both northern long-eared and Indiana bats may be possible. Such approaches would allow land managers to manage for both northern long-eared bat habitat and other objectives. However, the nature of targeted management approaches employed likely will depend on the unique forest context and dynamic within which individual colonies reside. / Ph. D.
33

Acoustic sampling considerations for bats in the post-white-nose syndrome landscape

Barr, Elaine Lewis 27 January 2020 (has links)
Bat populations across North America are either facing new threats from white-nose syndrome (WNS) and wind energy development or have already experienced precipitous declines. Accordingly, researchers and managers need to know how to best monitor bats to document population and distribution changes, as well as where to look for persisting populations. Landscape-scale WNS impacts to summer bat populations are not well understood, and although acoustic monitoring is commonly used to monitor these populations, there is limited information about differences among acoustic detectors and the implications to managers thereof. My objectives were to model the relationship between WNS impact, influence of available hibernacula, and environmental factors for summer nightly presence of three WNS-affected bats and to compare how multiple models of acoustic detectors perform in terms of detection probability and nightly recorded bat activity. I collected acoustic data from 10 study areas across Virginia, West Virginia, Ohio and Kentucky to describe changes in nightly presence of WNS-affected bat species during summer 2017. During the same period of time, I compared five types of acoustic detectors at Fort Knox, Kentucky. My results show the potential efficacy of using a WNS impact-year metric to predict summer bat presence, and highlight which environmental variables are relevant for large-scale acoustic monitoring. Additionally, my findings suggest that each of the detector types tested would suffice for most research and monitoring activities, but standardization of detector type within the scope of a project or study should be encouraged. / Master of Science / Bat populations across North America are either facing new threats from white-nose syndrome (WNS) and wind energy development or have already experienced devastating declines. Accordingly, wildlife biologists need to know how to best monitor bats to document population and distribution changes, as well as where to look for remaining populations. Landscape-scale WNS impacts to summer bat populations are not well understood, and although acoustic technology is commonly used to monitor these populations, there is limited information about differences among acoustic detectors and the implications to managers thereof. My objectives were to model the relationship between WNS impact, influence of available bat hibernation caves, and environmental factors for summer nightly presence of three WNS-affected bats and to compare how multiple models of acoustic detectors perform in terms of detection probability and nightly recorded bat activity. I collected acoustic data from 10 study areas across Virginia, West Virginia, Ohio and Kentucky to describe changes in nightly presence of WNS-affected bat species during summer 2017. During the same period of time, I compared five types of acoustic detectors at Fort Knox, Kentucky. My results show potential viability of a WNS impact-year metric to predict summer bat presence, and highlight which environmental variables are relevant for large-scale acoustic monitoring. Additionally, my findings suggest that each of the detector types tested would suit most research and monitoring activities, but standardization of detector type within the scope of a project or study should be encouraged.
34

ROOSTING BEHAVIOR, HABITAT USE, AND RELATIVE ABUNDANCE OF THE NORTHERN LONG-EARED BAT (<em>MYOTIS SEPTENTRIONALIS</em>) FOLLOWING ARRIVAL OF WHITE-NOSE SYNDROME TO MAMMOTH CAVE NATIONAL PARK

Thalken, Marissa M. 01 January 2017 (has links)
White-Nose Syndrome (WNS; Pseudogymnoascus destructans) is responsible for the regional population collapse of many cave-hibernating bat species, including the northern long-eared bat (Myotis septentrionalis), in eastern United States and Canada. I evaluated roosting behavior, habitat selection, and landscape-scale distribution of roosts of the northern long-eared bat during spring emergence and the early maternity season in Mammoth Cave National Park, Kentucky, USA, from 2015 to 2016. Logistic regression analysis comparing habitat features of roosts with random plots indicated selection of roosts reflected the costs of energetic demands by sex and reproductive status. Relative abundance of local bat species was assessed pre- and post-arrival of WNS in the Park during the summer season, with capture rates observed during the progression of WNS indicating that the fungal disease led to declines in the overall abundance of several bat species on the summer landscape, especially the northern long-eared bat. Distributional trends were quantified using spatial point pattern analysis which indicated that bats had clear roosting patterns associated with landscape level features and habitat resources. Monitoring bat populations regionally and at local scales will be imperative to helping conservation efforts for several bat species most affected by WNS.
35

Diets of bats in West Virginia

Burke, Theresa Sydney. January 2002 (has links)
Thesis (M.S.)--Marshall University, 2002. / Title from document title page. Document formatted into pages; contains vi, 50 p. with illustrations and maps. Includes bibliographical references (p. 22-26).
36

The Impact of Climate on the Population of Indiana Bat (Myotis Sodalis)

lemzouji, Khalid Unknown Date
No description available.
37

Determining energy conservation during torpor for three Myotis species and response of Myotis species to human disturbance while day roosting

Sichmeller, Timothy J. January 2010 (has links)
The endangered Indiana bat (Myotis sodalis) has been the focus of much research in the past 40 years, primarily with respect to the summer habitat requirements for the species. Recent advances in radio telemetry have allowed researchers to learn about the specific activity patterns for roosting bats. Torpor is an energetic process that bats use to conserve energy through the day. We used an equation that gives a threshold for when the animal enters torpor to quantify the amount of energy conservation among Indiana bats, northern long-eared bat (M. septentrionalis) and little brown bat (M. lucifugus) and their reproductive stage. Additionally, we used the torpor threshold to determine if researchers were causing disturbances to roosting female Myotis bats in the summer. / Department of Biology
38

The Impact of Climate on the Population of Indiana Bat (Myotis Sodalis)

lemzouji, Khalid 11 1900 (has links)
The Indiana Bat (Myotis sodalis) population had decreased by 56% between 1967 and 2006. In summer 2006, a mysterious disease called White Nose Syndrome was first identified. Since then, the disease killed almost one million bats in North America. Many Biologists believe that both the population decrease before the appearance of the disease and WNS are associated with climate. In a joined effort with Yellowstone Ecological Research Center (YERC), US Fish and Wildlife Service (USFWS) and NASA Terrestrial Observation and Prediction System (TOPS), our study is a partial population viability analysis which aims to establish a link between bat population dynamic and climate before the appearance of WNS. / Biostatistics
39

Availability and seasonal use of diurnal roosts by Rafinesque's big-eared bat and southeastern myotis in bottomland hardwoods of Mississippi

Stevenson, Candice LeeAnn, January 2008 (has links)
Thesis (M.S.)--Mississippi State University. Department of Wildlife and Fisheries. / Title from title screen. Includes bibliographical references.
40

Ciclo reprodutivo dos machos de Myotis lavali e Molossus molossus (Mammalia: Chiroptera) em um fragmento de mata atlântica, nordeste do Brasil

ARANDAS, Maria Juliana Gomes 20 February 2018 (has links)
Submitted by Mario BC (mario@bc.ufrpe.br) on 2018-05-14T12:33:41Z No. of bitstreams: 1 Maria Juliana Gomes Arandas.pdf: 4922822 bytes, checksum: 148127b0ff232a5523d17669ea5ab23c (MD5) / Made available in DSpace on 2018-05-14T12:33:41Z (GMT). No. of bitstreams: 1 Maria Juliana Gomes Arandas.pdf: 4922822 bytes, checksum: 148127b0ff232a5523d17669ea5ab23c (MD5) Previous issue date: 2018-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Bats have peculiar reproductive aspects that evolved in order to adapt to different environmental and climatic conditions. One of the criteria for the understanding about the reproductive biology in bats is the testicular and epididymal morphophysiology. Molossus molossus and Myotis lavali are insectivorous bats, and studies on the reproductive biology of these species are scarce, especially in the Northeast of Brazil. Therefore, it was analyzed the testicular and epididymal histomorphometry as well as testosterone levels of M. molossus and M. lavali from a fragment of Atlantic Forest located between the cities of Tamandaré and Rio Formoso-PE. In total, 23 adult males of M. molossus were studied, being 10 for dry months and 13 for rainy months. Besides that, 34 adult males of M. lavali were analyzed (22 in dry months and 12 in rainy months). After Anesthesia, blood samples were collected to testosterone dosage. Subsequently, the testicles and epididymides were fixed in 10% buffered formalin, and submitted to the routine histological techniques. For the testicles, the following histomorphometric parameters were evaluated: the tubular and intertubular areas, quantification of spermatocytes, rounded and elongated spermatids, Sertoli cells and Leydig cells, while in the epididymis: the tubular, luminal and epithelial areas from the head, body and tail. The results indicated that M. molossus presented higher averages for the tubular and intertubular areas, rounded and elongated spermatids, Leydig cells and testosterone levels. In the epididymis, the tubular, luminal and epithelial areas were larger in rainy months. On the other hand, M. lavali exhibited increased tubular and intertubular areas, number of elongated spermatids, Sertoli cells, Leydig cells and testosterone levels as well as tubular, luminal and epithelial area of the head and tail of the epididymis during the rainy season. Physiologically, males of both species have a high investment in the final stages of spermatogenesis and in the concentration of testosterone. Furthermore, the two species have a greater capacity to store spermatozoa in the region of the tail of epididymis, which relates to the reproductive strategy developed by bats for storage. Although both species exhibit a continuous spermatogenic cycle, it is noted that they adjust their reproduction for the rainy months. / Os morcegos apresentam aspectos reprodutivos peculiares que evoluíram a fim de se ajustar as diferentes condições ambientais e climáticas, e um dos critérios para o conhecimento da reprodução é a morfofisiologia testicular e epididimária. Molossus molossus e Myotis lavali são espécies de morcegos insetívoros, e os estudos referentes a biologia reprodutiva são escassos, principalmente no Nordeste do Brasil. Assim, analisou-se a histomorfometria testicular e epididimária, assim como os níveis de testosterona de M. molossus e M. lavali em um fragmento de Mata Atlântica localizado entre os Municípios de Tamandaré e Rio Formoso-PE. Um total de 23 machos adultos foi selecionado para M. molossus, sendo 10 em meses secos e 13 para meses chuvosos. Ao passo que foram utilizados 34 machos adultos para M. lavali, sendo 22 em meses secos e 12 em meses chuvosos. Após anestesia, as amostras de sangue foram coletadas para a dosagem de testosterona. Os testículos e epidídimos foram removidos e fixados em formal 10% tamponado, e posteriormente submetidos à técnica histológica de rotina. Para o testículo, os seguintes parâmetros histomorfométricos foram avaliados: a área tubular, área intertubular, quantificação dos espermatócitos, espermátides (arredondadas e alongadas), células de Sertoli e células de Leydig, enquanto que no epidídimo: as áreas tubular, luminal e epitelial da cabeça, corpo e cauda. Os resultados indicaram que M. molossus apresentou maiores médias para a área tubular, intertubular, espermátides (arredondadas e alongadas), células de Leydig e níveis de testosterona. No epidídimo, as áreas tubular, luminal e epitelial foram maiores em meses chuvosos. Ao passo que M. lavali na estação chuvosa exibiu um aumento nas áreas tubular e intertubular, nas espermátides alongadas, células de Sertoli, células de Leydig e nos níveis de testosterona, assim como na área tubular, luminal e epitelial da cabeça e cauda do epidídimo. Fisiologicamente, os machos das duas espécies têm um alto investimento nas etapas finais da espermatogênese e na concentração de testosterona. Atrelado a isso, nota-se uma maior capacidade de comportar os espermatozoides na região da cauda do epidídimo, que se relaciona a estratégia reprodutiva desenvolvida pelos morcegos para a estocagem. Embora as duas espécies apresentem um ciclo espermatogênico contínuo, nota-se que ajustam a reprodução para os meses chuvosos.

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